﻿using System;

class PrintASequence
{
    static void Main()
    {
        int number = 2;
        for (int i = 0; i < 10; i++)
        {
            if (i % 2 == 0)
            {
                Console.Write("{0} ", number);
            }
            else
            {
                Console.Write("-{0} ", number);
            }
            number++;
        }
        Console.WriteLine();
    }
}